-- is big news today in the world of books the best selling author of our time by a mile is back at her keyboard. JK -- imagination behind Harry Potter is writing her first novel since -- completed the potter series five years ago. And justice her boy wizard has grown up and moved on so has rolling. As ABC's Dan Harris reports her new book is aimed at adults. JK Rowling's Harry Potter books about a boy wizard cast -- powerful spelled not only getting millions of kids interested in reading. It was. But also becoming the most successful publishing franchise ever. So -- 415. Million copies. The movies -- -- largest grossing franchise in history taking in seven point seven. Billion dollars but her new book for grownups that's pretty much a blank page we don't know what it's called what it's about or when it's coming out. All we do know is what Roland said in a statement my next book will be very different -- -- Harry Potter series. -- potter books made a single mom on welfare wealthier than the queen of England. Can she really make this which had grown out literature. Rowling herself seem to have some -- when he finished the last of -- seven potter books. In 2007. I didn't look forward to and -- two post Khatami -- For the same time in my trip leaving her. It is true that children's authors rarely succeed in adult literature. Deborah JK Rollins isn't any other author Scott such -- -- -- franchise since that guaranteeing. You know biggest book of the year as he points out millions of adults read a potter books on plants in secret and so many of those children who grew up on -- books. Are now grown -- themselves. In fact the very first book begins with Harry -- eleventh birthday. He would be 26. Today. In Harris ABC news.

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